It has been discovered by agricultural scientists that corn cobs are of considerable nutritional value as cattle feed and that the conventional practice of leaving the cobs in the field and harvesting only the kernels of shelled corn results in a loss of at least 20% of the potential nutritional value of the crop. Harvesting of the cobs is a problem, however, because equipment manufacturers have not as of this time designed implements specifically for the purpose of harvesting corn cobs. The present invention provides an inexpensive means for converting a conventional combine so that it will collect cobs along with the corn kernels. By use of the device of the present invention a conventional combine which normally retains the corn and discharge the cob back onto the field is converted into a machine capable of collecting both in the grain tank while the rest of the corn plant and other debris is discharged back onto the field.
An important object of the invention is to replace both the chaffer and sieve from the final cleaning stage of the combine and replace them with an element adapted to harvest corn cobs along with the kernels. Further objects include provision of such elements which are designed to allow the lighter crop residue such as the stocks and leaves of the corn plant to be shaken and blown out the rear of the combine. The preferred embodiment also helps direct the flow of air from the blower fan of the combine improving efficiency and reducing fuel consumption by permitting slower fan and cylinder speeds.
A further object is to replace the chaffer and sieve of units of combine with a flat-surfaced element having numerous perforations therethrough of a size sufficient to permit corn cob particles to fall through said perforations, the element being provided with fins protruding from the upper surfaces thereof to assist and channel the flow of materials thereover and further being provided with reinforcing means including downwardly projecting side members and crosswardly extending ribs across the bottom surface thereof which ribs are preferrably equal to direct the flow of air through the element.
Another benefit of the invention is that the amount of voluntary corn growing in the field the following year is curtailed, due to reduction in the amount of corn and cobs with corn left on them is left in the field compared with conventional sieve and chaffer methods. Another advantage is improved fuel efficiency. The concaves are opened up, putting less stress on the combine, and cylinder speed tuned down therefore reducing fuel consumption.